Moonstone

Real mineral · uncommon · KAlSi₃O₈

A feldspar exhibiting adularescence, a floating blue or white sheen caused by light scattering between alternating layers of orthoclase and albite. Named for its resemblance to moonlight on water.

Identity

Formula

KAlSi₃O₈

Chemical class

silicate

Mineral group

Albite, Labradorite, Sunstone

Also known as

Adularia, Hecatolite

Crystallography

Crystal system

monoclinic

Habits

tabular, massive

Fracture

uneven

Physical properties

Mohs hardness

6

Density

2.56 g/cm³

Luster

vitreous, pearly

Colors

colorless, white, gray, blue, pink

Streak

white

Transparency

transparent, translucent

Geology

Origins

igneous

Host rocks

pegmatite, granite

Associated minerals

Quartz, feldspar, Tourmaline

Geography

Sri Lanka, India, Myanmar, Brazil, Madagascar

Classification

Rarity

uncommon

Gem quality

Yes

Arcane properties

Affinity

water, time

Effects

illusion, scrying

Planar origin

Material Plane

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